Molded plastic front section for card tray and associated follower rod front end portion

ABSTRACT

A molded plastic front section for a card tray is formed by joining a single rear panel to a multi-part or composite front panel assembly; the assembly comprising central, upper and lower panel elements. The central panel element cooperates with the upper and lower panel elements to form a front surface of the front section and a tray contents identifying card receiving slot extending horizontally transversely of such front surface, and defines an essentially U-shaped drawer pull arranged to extend vertically and bridge across the receiving slot. The lower portion of the drawer pull and the front surface are formed with aligned apertures to slideably receive the front end portion of a follower rod; such front end being of variable cross-sectional configuration lengthwise thereof to both conform to the profile of the drawer pull and to define an upstanding pull tab therefor.

United States Patent [191 Little 1 1 MOLDED PLASTIC FRONT SECTION FOR CARD TRAY AND ASSOCIATED FOLLOWER ROD FRONT END PORTION [75] Inventor: Carl B. Little, Jamestown. NY.

[73] Assignee: Weber Knapp Company,

Jamestown, NY.

[22] Filed: Aug. 8, 1973 [21] Appl. No.: 386,540

[52] U.S. Cl. 402/61; 402/502; 40/325; 3l2/234.l; 312/320 [51] Int. Cl 1342f 13/14 [58] Field of Search 402/50261', 312/330, 320, 312/234, 234.1, 189; 40/325, 312

May 13, 1975 Attorney, Agent, or FirmBean & Bean [57] ABSTRACT A molded plastic front section for a card tray is formed by joining a single rear panel to a multi-part or composite front panel assembly; the assembly comprising central, upper and lower panel elements. The central panel element cooperates with the upper and lower panel elements to form a front surface of the front section and a tray contents identifying card receiving slot extending horizontally transversely of such front surface, and defines an essentially U-shaped drawer pull arranged to extend vertically and bridge across the receiving slot. The lower portion of the drawer pull and the front surface are formed with aligned apertures to slideably receive the front end portion of a follower rod; such front end being of variable cross-sectional configuration lengthwise thereof to both conform to the profile of the drawer pull and to define an upstanding pull tab therefor.

6 Claims, 6 Drawing Figures MOLDED PLASTIC FRONT SECTION FOR CARD TRAY AND ASSOCIATED FOLLOWER ROD FRONT END PORTION SUMMARY OF THE INVENTION The present invention is generally directed towards a molded plastic front section of the type employed in combination with a tray section to form a library or like card file tray.

More particularly, the present invention is directed towards a card tray front section featuring a front surface recessed to define a horizontally extending tray contents identifying card receiving slot or recess and an essentially U-shaped drawer pull vertically bridging such slot. The front section is defined by joining a generally rectangular rear panel to a novel multi-part or composite front panel assembly; the assembly serving to define both a pull for the drawer and a slot for removably receiving a tray contents identifying card.

More specifically, the front panel assembly includes separately molded central, upper and lower panel elements. The central panel element includes a forwardly facing band portion arranged to extend horizontally across the front section, upper and lower connecting portions arranged to upstand and depend from adja cent a mid-point of the band portion, and an essentially U-shaped drawer pull end connected to upper and lower extremities of the connecting portions, so as to forwardly overlie or bridge the band portion. The upper and lower panel elements are fixed to overlie the upper and lower connecting portions of the central panel element and cooperate with its band portion to form the forwardly facing surface of the front section, as well as to define a transversely extending tray contents identifying card receiving recess.

The drawer pull, the lower panel element and the lower connecting portion are formed with aligned apertures to slideably receive a front end portion of the follower rod. It is a particularly important feature of the present invention that the rod front end portion is of variable cross-sectional configuration in a direction lengthwise thereof, whereby to conform to the profile of the drawer pull. This construction provides for proper location of the follower rod without interfering with the proper grasping of the drawer pull, and permits the front end of the follower rod to be formed with an upstanding pull tab facilitating withdrawal and manipulation of the follower rod.

The front section of the present section may be affixed to the front wall of a tray section to complete a library or like card file tray in the manner described in my prior U.S. Pat. No. 3,666,341, and may be fitted with a follower rod retaining latch device in the manner described in my US. Pat. No. 3,732,0l9.

DRAWINGS The nature and mode of operation of the present invention will now be more fully described in the following detailed description taken with the accompanying drawings wherein:

FIG. 1 is a perspective view ofa library card tray featuring the front section of the present invention;

FIG, 2 is an exploded perspective view of the front section, as viewed from the front;

FIG. 3 is an exploded perspective view of the front section, as viewed from the rear;

FIG. 4 is a side elevational view of the front section,

FIG. 5 is a sectional view taken generally along line 55 in FIG. I; and

FIG. 6 is a bottom plan view of the front section.

DETAILED DESCRIPTION Reference is now made particularly to Flg. I, wherein a library or like card file tray 10 is shown as generally including a front section 12; a tray section 14; and a follower rod 16 for use in stringing apertured cards, not shown, stored within the tray section. Tray 10 is completed by a latch device 18, shown only in FIGS. 2 and 6, which is employed to releasably latch or retain follower rod 16 in a fully inserted position best shown in FIG. 1.

By now referring to FIGS. 2 and 3, it will be understood that in accordance with the present invention, front section 12 is formed by suitably joining. as by ultrasonic welding, solvent, adhesive or heat bonding techniques, a single, generally rectangular molded plastic rear panel 20 and a composite front panel assembly 22, which is in turn defined by separately formed molded plastic central, upper or top and lower or bottom panel elements 24, 26 and 28, respectively.

Rear panel 20 is quite similar in many respects to those described in my prior U.S. Pat. No. 3,666,341 and my copending application Ser. No. [25,493, filed Mar. l8, l97l. In this respect, panel 20 is formed with a plurality of forwardly projecting lugs 30. which serve to mount a pair of generally L-shaped metal reinforcing and mounting insert plates 32, a through opening 34, which is dimensioned to freely receive follower rod 16; and a plurality of mounting apertures 36. Screw devices 38, which are shown only in FIG. 5, may be passed successively through tray section front wall apertures, not shown, rear panel apertures 36 and then threadably secured within insert plate apertures 40, in order to clamp sections 12 and 14 together in a tray assembled relationship.

The design oflatch device 18 and the mode of installing and retaining same within front section 12 may be identical to that described in my above mentioned copending patent application. Thus, it is sufficient to the overall understanding of the present invention to merely indicate that latch device 18 includes a stationary mounting part 42 and a manually operable latch lever 44, which is pivotally secured to mounting part 42 and removably receivable within slot 46 of follower rod front end or head end portion 48 for the purpose of releasably retaining the follower rod in its fully inserted position shown in FIG. 1. An opening generally designated as 50in FIG. 6, and shown as being located in the bottom wall or surface of front section 12 affords access to latch lever 44. Further, it will be understood that a coil or like compression spring, not shown, is normally positioned within opening 34 intermediate sections 12 and 14 for the purpose of forcing follower rod 16 forwardly from its fully inserted position when latch lever 44 is manually pivoted from within follower rod front end slot 46.

Again referring particularly to FIGS. 2 and 3, it will be understood that central panel element 24 is shaped to define a generally rectangular band portion 52, which extends horizontally between spaced vertically disposed central side wall portions 54 of front section 12; upper and lower connecting portions 56 and 58, which upstand and depend, respectively, from adjacent the mid-point of band portion 52', and an essentially U- shaped drawcr pull 60, which has its upper and lower ends connected to the upper and lower extremities of connecting portions 56 and 58, respectively, such as to forwardly overlie and bridge band portion 52. More specifically, band portion 52 defines a forwardly facing convex guide or support surface 62, which is vertically bounded by upper and lower reinforcing and attaching ribs 64 and 66, which in turn serve to define facing upper and lower guide or stop surfaces 640 and 66a, respectively.

Upper connecting portion 56 includes a front flange portion 68, which is formed with an aperture 70 to accommodate a portion of a pull rear surface forming die, during the molding operation; a plurality of vertically rising reinforcing and attaching ribs 72; and a horizontally extending reinforcing rib 74.

Lower connecting portion 58 includes a front flange 76, which is formed with an opening 78 for receiving follower rod front end portion 48 and with latch device positioning ribs 80', a pair of vertically disposed reinforcing and attaching ribs 82', and a central bottom wall portion 84 of front section 12. As best shown in FIGv 6, central bottom wall portion 84 is cut away so as to partially define access opening 50.

Pull 60 is best shown in FIGS, l-3 as having its upper leg or top portion 86 arranged to overlie upper connecting portion rib 74 and define a central top portion of front section 12. The lower leg or bottom portion 88 of pull 60 has a lower surface arranged to lie essentially flush with central bottom wall portion 84 and has an upper surface shaped to define an upwardly opening guide recess 90 aligned with a generally rectangular opening 92 formed in the upstanding pull or leg connecting portion 94 of the pull, It will be noted upon viewing FIGS. 4 and 5 that the upper or inner surfaces 88a of lower leg portion 88 are disposed substantially below the top or upper end of leg connecting portion opening 92, whereas the lower surface of recess 90 is disposed essentially flush with the bottom or lower end of opening 92. In other words, the height of guide recess 90 is substantially less than the height of opening 92.

Upper panel element 26 is formed with a generally rectangular front flange 96, which has a lower marginal edge thereof reinforced by an attaching rib 98 and extends horizontally between spaced vertically disposed upper side wall portions 100 of front section 12; and horizontally spaced top wall portions 102 of front section 12. As best shown in FlGs. 1-3, front flange 96 is partially cut away, as at 104 to permit fitting thereof upwardly beneath pull upper leg portion 86 in order to position wall portions 102 in a coplanar relationship with the upper surface of pull leg portion 86.

Lower panel element 28 is formed with a generally rectangular front flange portion 108, which has an upper marginal edge thereof formed to define an attaching rib vertically disposed lower side wall portions 112 of front section 12; and horizontally spaced bottom wall portions 114 of front section 12. As best shown in FIGS. 1-3 and 6, front flange portion 108 is cut away to define an opening 116, to permit fitting thereof downwardly over pull lower leg portion 88 in order to position wall portions 114 in a coplanar relationship with central bottom wall portion 84. When the panel elements are assembled, opening 116 is aligned with the pull opening, which is defined by leg connecting portion opening 92 and recess 90, and lower connecting portion opening 78. As a practical matter, the

portion of opening 116 disposed above the base of recess 90 may be considered as defining an opening 91 extending through the front surface of the front sec- 5 tion,

When panel elements 24, 26 and 28 are assembled to form a completed front panel assembly 22, there is defined an open ended slot 118, which extends transversely of the front surface of the front section for removably accommodating a drawer contents indicia card, not shown. Referring specifically to FIG. 5, it will be understood that slot 118 is rearwardly bounded by guide surface 62, vertically bounded by guide surfaces 64a and 66a and forwardly bounded by the rear surfaces of ribs 98 and 110.

Also, when panel elements 24, 26 and 28 are assem bled, undercuts 120 formed along the rear edges of pull upper leg portion 86 and top wall portions 102 are dis posed in horizontal alignment; undercuts 122 formed along the rear edges of associated central, upper and lower wall portions 54, 100 and 112 are disposed in vertical alignment; and undercuts 124 formed along the rear edges of central wall portion 84 and bottom wall portions 114 are disposed in horizontal alignment Thus, undercuts 120, 122 and 124 cooperate to form a generally rectangular recess for slideably receiving the marginal edges of rear panel 20, such that the rear surface of the rear panel is disposed to lie in a flush relationship with the rear marginal edge surfaces of the front panel assembly when front section 12 is fully assembled. Front section 12 may be permanently maintained in an assembled condition by suitably joining the marginal edges of rear panel 20 to the marginal edge portions of assembly 22, which define undercuts 120, 122 and 124', by suitably joining the rear edge surfaces of ribs 64, 72 and 82 to the front surface of rear panel 20; and by suitably joining the rear surfaces of ribs 98 and 110 to the front surfaces of ribs 64 and 66. As indicated above, joining may be accomplished in any suitable manner, such as by ultrasonic welding, solvent, adhesive or heat bonding techniques.

By forming front panel assembly 22 from panel elements 24, 26 and 28, the forwardly facing surfaces of panel elements 26 and 28 and recessed area 94a of pull connecting portion 94 may be roughened" or texturized" while remaining surfaces remain smooth".

Again referring to FIGS. 1-3 and 5, it will be understood that a further feature of the present invention is the specific construction of follower rod front end portion 48, and the manner in which it is associated with drawer pull 60. In this respect, end portion 48 is somewhat U-shaped in side elevation in that it is formed with enlarged or vertically upstanding portions and 142, which are dimensioned to be slideably received within pull connecting portion opening 92 and front section opening 91, respectively; and a bridging or connecting portion 144, which is dimensioned to be slideably received within guide recess 90. As will be apparent, rear portion 142 is necessarily of a size equal to or less than the size of front portion 140 in order to permit movement of the former forwardly through opening 92.

When the follower rod is fully inserted, front portion 140 conforms to and lies wholly within pull connecting portion 94, i.e., its lengthwise dimension being such that its front face or surface 140a is disposed essentially flush with the surface of recessed area 940 when its upstanding rear surface 14021 is arranged essentially flush with or slightly forwardly of the rear surface 94b of the pull leg connecting portion; rear portion 142 conforms to front section opening 91 and has an upstanding front face or surface 142a disposed essentially flush with the front face of lower panel element 28; and bridging portion 144 conforms to and lies wholly within guide recess 90 with its upper surface 144a disposed essentially flush with the upper or inner surfaces 880 of pull lower leg portion 88. Thus, when the follower rod is fully inserted, the whole of end portion 48 is hidden by assembly 22 when viewed from either side and does not diminish the space available for manually gripping pull 60. Moreover, end portion 48 is essentially hidden when the front section is viewed from the front or in front perspective, particularly when surface 140a is roughened" to correspond to the finish applied to recess 94a.

When latch lever 44 is released, the resultant spring biased forward movement of the follower rod serves to position rear face or surface 140!) forwardly of pull 60. In that rear surface 140!) upstands from surface 1440, the former provides a convenient pull" or pressure" surface, which can be conveniently engaged by the finger of an operator for the purpose of completing removal of the follower rod from within the tray. Also, it will be noted that surfaces 140b, 142a and 1440 cooperate to define a convenient gripping recess in front end portion 48 for receipt of the finger of an operator to facilitate carrying and manipulation of the follower rod. This gripping recess is particularly advantageous in that conventional front end portions of follower rods are difficult to properly grip because of their small size and the fact that they are today commonly formed of smooth surfaced plastic material.

As will be apparent, the disclosed configuration of follower rod front end portion 48 and associated portions of pull 60 possess utility in any card tray construction where it is desirable to hide the front end portion when the follower rod is fully inserted, while providing such front end portion with a pull" surface to facilitate withdrawal of the follower rod. Moreover, where dictated by design and permitted by strength considerations, the upper leg portion of the pull may be omitted in order to provide a pull of a generally L- shaped configuration.

I claim:

1. In a card tray construction having separately formed front and tray sections, means for connecting a front of said tray section to a rear of said front section to form a completed card tray, and a follower rod rearwardly insertable through said front and tray sections for the purpose of removably supporting cards within said tray section, the improvement wherein said front section comprises in combination:

a generally rectangular rear panel and a generally rectangular composite front panel assembly joined to said rear panel to form said front section, said panel assembly including a central panel element, an upper panel element and a lower panel element, said central panel element having a horizontally extending central band portion, upper and lower connecting portions arranged to upstand and depend from adjacent a mid point of said band portion and an essentially U-shaped drawer pull end connected to upper and lower extremities of said connecting portions so as to forwardly bridge said band portion, said upper and lower panel elements forwardly overlying said upper and lower connecting portions and cooperating with said band portion to form a forwardly facing surface of said front section and to define an open ended recess extending transversely of said forwardly facing surface for receiving a tray contents identifying card, and said drawer pull and said lower panel element and said lower connecting portion and said rear panel are formed with substantially aligned openings for permitting passage of said follower rod rearwardly through said front section into an inserted position within said tray section.

2. The improvement according to claim 1, wherein said drawer pull includes upper and lower leg portions connected to said upper and lower connecting portions, respectively, and a leg connecting portion joining said upper and lower leg portions, said pull opening is defined by an opening through said leg connecting por tion disposed in alignment with said opening in said lower panel element and an upwardly opening guide recess formed in said lower leg portion and extending between said openings in said leg connecting portion and said lower panel element, upper surfaces of said lower leg portion bounding said guide recess being disposed substantially below an upper end of said leg connecting portion opening, and wherein said follower rod includes a front end portion defined by a front portion dimensioned to be slideably received within said leg connecting portion opening, a rear portion dimensioned to be slideably received within said lower panel element opening and a bridging dimensioned to be slideably received within said guide recess with an upper surface thereof arranged essentially flush with said upper surfaces of said lower leg portion, said front portion having upstanding front and rear surfaces arranged essentially flush with front and rear surfaces of said leg connecting portion when said follower rod is inserted, and said rear portion having an upstanding front surface arranged essentially flush with said forwardly facing surface of said front section when said follower rod is inserted.

3. In a card storage tray construction having a front including a pull projecting forwardly of a front surface thereof, a tray, a follower rod rearwardly insertable through an opening in the front and into the tray for the purpose of removably supporting cards within the tray, and means operable for releasably retaining the follower rod in an inserted position and upon release thereof biasing same forwardly from inserted position whereby to move a front end portion of said follower rod forward of said front to facilitate gripping of said front end portion by an operator, the improvement comprising in combination:

said pull includes a lower portion projecting forwardly of said front surface of said front from adjacent a lower marginal edge thereof and a pull portion upstanding from a forward end of said lower portion, said pull portion having an opening therethrough aligned with said front opening, and said lower portion having a vertically opening guide recess arranged in alignment with said openings and extending therebetween, said lower portion having upper surfaces thereof bounding said guide recess, said upper surfaces being disposed substantially below an upper end of said pull portion opening; and

said front end portion has front, rear and bridging portions, said front portion being slideably receivable within said pull portion opening and having a lengthwise dimension between front and rear faces thereof whereby the whole of said front portion lies between front and rear surfaces of said pull portion when said follower rod is inserted, said rear portion being slideably receivable within said front opening and being disposed rearwardly of said front surface of said front for engagement with said means when said follower rod is inserted and said bridging portion being slideably receivable within said guide recess and having an upper surface thereof arranged essentially flush with said upper surfaces of said lower portion when said follower rod is inserted, and said rear face of said front portion upstanding from said upper surface of said bridging portion.

4. The improvement according to claim 3, wherein said rear portion has a front face upstanding from said upper surface of said bridging portion, and said front face of said rear portion is disposed essentially flush with said front surface of said front when said follower rod is inserted.

5. A card storage tray comprising in combination:

a front having an opening extending rearwardly through a front surface thereof;

a card tray fixed to said front and extending rearwardly thereof;

a pull fixed to said front and projecting forwardly thereof, said pull having a lower portion projecting forwardly of said front surface and a pull portion upstanding from a forward end of said lower portion, said pull having an opening extending rear wardly therethrough in alignment with said front opening, said pull opening being defined by an opening in said pull portion and an upwardly opening recess extending lengthwise of said lower portion between said pull portion and said front, said recess having a height substantially less than the height of said pull portion opening; and

a follower rod removably insertable rearwardly through said pull and said front openings and into said card tray for removing storing cards within said card tray, said follower rod having a front end portion including a front portion conforming to said pull portion opening and being wholly within said pull portion when said follower rod is inserted, a rear portion conforming to said front opening and being disposed rearwardly of said front surface of said front when said follower rod is inserted and a bridging portion for connecting said front and rear portions, said bridging portion conforming to said recess and being wholly within said lower portion when said follower rod is inserted.

6. A card storage tray according to claim 5, wherein said front and rear portions of said front end portion have rear and front faces, respectively, arranged to upstand from an upper surface of said bridging portion, said front face of said rear portion is disposed essentially flush with said front surface of said front when said follower rod is inserted, and said front portion additionally includes a front face disposed essentially flush with a front surface of said pull portion when said follower rod is inserted 

1. In a card tray construction having separately formed front and tray sections, means for connecting a front of said tray section to a rear of said front section to form a completed card tray, and a follower rod rearwardly insertable through said front and tray sections for the purpose of removably supporting cards within said tray section, the improvement wherein said front section comprises in combination: a generally rectangular rear panel and a generally rectangular composite front panel assembly joined to said rear panel to form said front section, said panel assembly including a central panel element, an upper panel element and a lower panel element, said central panel element having a horizontally extending central band portion, upper and lower connecting portions arranged to upstand and depend from adjacent a mid point of said band portion and an essentially U-shaped drawer pull end connected to upper and lower extremities of said connecting portions so as to forwardly bridge said band portion, said upper and lower panel elements forwardly overlying said upper and lower connecting portions and cooperating with said band portion to form a forwardly facing surface of said front section and to define an open ended recess extending transversely of said forwardly facing surface for receiving a tray contents identifying card, and said drawer pull and said lower panel element and said lower connecting portion and said rear panel are formed with substantially aligned openings for permitting passage of said follower rod rearwardly through said front section into an inserted position within said tray section.
 2. The improvement according to claim 1, wherein said drawer pull includes upper and lower leg portions connected to said upper and lower connecting portions, respectively, and a leg connecting portion joining said upper and lower leg portions, said pull opening is defined by an opening through said leg connecting portion disposed in alignment with said opening in said lower panel element and an upwardly opening guide recess formed in said lower leg portion and extending between said openings in said leg connecting portion and said lower panel element, upper surfaces of said lower leg portion bounding said guide recess being disposEd substantially below an upper end of said leg connecting portion opening, and wherein said follower rod includes a front end portion defined by a front portion dimensioned to be slideably received within said leg connecting portion opening, a rear portion dimensioned to be slideably received within said lower panel element opening and a bridging dimensioned to be slideably received within said guide recess with an upper surface thereof arranged essentially flush with said upper surfaces of said lower leg portion, said front portion having upstanding front and rear surfaces arranged essentially flush with front and rear surfaces of said leg connecting portion when said follower rod is inserted, and said rear portion having an upstanding front surface arranged essentially flush with said forwardly facing surface of said front section when said follower rod is inserted.
 3. In a card storage tray construction having a front including a pull projecting forwardly of a front surface thereof, a tray, a follower rod rearwardly insertable through an opening in the front and into the tray for the purpose of removably supporting cards within the tray, and means operable for releasably retaining the follower rod in an inserted position and upon release thereof biasing same forwardly from inserted position whereby to move a front end portion of said follower rod forward of said front to facilitate gripping of said front end portion by an operator, the improvement comprising in combination: said pull includes a lower portion projecting forwardly of said front surface of said front from adjacent a lower marginal edge thereof and a pull portion upstanding from a forward end of said lower portion, said pull portion having an opening therethrough aligned with said front opening, and said lower portion having a vertically opening guide recess arranged in alignment with said openings and extending therebetween, said lower portion having upper surfaces thereof bounding said guide recess, said upper surfaces being disposed substantially below an upper end of said pull portion opening; and said front end portion has front, rear and bridging portions, said front portion being slideably receivable within said pull portion opening and having a lengthwise dimension between front and rear faces thereof whereby the whole of said front portion lies between front and rear surfaces of said pull portion when said follower rod is inserted, said rear portion being slideably receivable within said front opening and being disposed rearwardly of said front surface of said front for engagement with said means when said follower rod is inserted and said bridging portion being slideably receivable within said guide recess and having an upper surface thereof arranged essentially flush with said upper surfaces of said lower portion when said follower rod is inserted, and said rear face of said front portion upstanding from said upper surface of said bridging portion.
 4. The improvement according to claim 3, wherein said rear portion has a front face upstanding from said upper surface of said bridging portion, and said front face of said rear portion is disposed essentially flush with said front surface of said front when said follower rod is inserted.
 5. A card storage tray comprising in combination: a front having an opening extending rearwardly through a front surface thereof; a card tray fixed to said front and extending rearwardly thereof; a pull fixed to said front and projecting forwardly thereof, said pull having a lower portion projecting forwardly of said front surface and a pull portion upstanding from a forward end of said lower portion, said pull having an opening extending rearwardly therethrough in alignment with said front opening, said pull opening being defined by an opening in said pull portion and an upwardly opening recess extending lengthwise of said lower portion between said pull portion and said front, said recess having a height substantially less than the height oF said pull portion opening; and a follower rod removably insertable rearwardly through said pull and said front openings and into said card tray for removing storing cards within said card tray, said follower rod having a front end portion including a front portion conforming to said pull portion opening and being wholly within said pull portion when said follower rod is inserted, a rear portion conforming to said front opening and being disposed rearwardly of said front surface of said front when said follower rod is inserted and a bridging portion for connecting said front and rear portions, said bridging portion conforming to said recess and being wholly within said lower portion when said follower rod is inserted.
 6. A card storage tray according to claim 5, wherein said front and rear portions of said front end portion have rear and front faces, respectively, arranged to upstand from an upper surface of said bridging portion, said front face of said rear portion is disposed essentially flush with said front surface of said front when said follower rod is inserted, and said front portion additionally includes a front face disposed essentially flush with a front surface of said pull portion when said follower rod is inserted. 